Baseline characteristics of mutation carriers who did and did not develop HCM
| Developed HCM N=4 | No HCM N=34 | p Value | |
|---|---|---|---|
| Age, years (range) | 13.8 (3.9) (9–17) | 16.0 (9.0) (5–39) | 0.62 |
| Female/male, n | 1/3 | 21/13 | 0.29 |
| Body surface area, m2 | 1.95 (0.14) | 1.64 (0.05) | 0.06 |
| Max LVWT, mm | 9.1 (0.3) | 7.9 (0.2) | <0.001 |
| Max LVWT z-score | 0.87 (0.35) | 0.24 (0.20) | 0.10 |
| Echo LVEF, % | 74 (2) | 69 (1) | 0.02 |
| Global E′ velocity, cm/s | 11.2 (0.5) | 14.8 (0.4) | <0.001 |
| Global S′ velocity, cm/s | 10.2 (0.6) | 10.1 (0.2) | 0.86 |
| Mean mitral ALL, mm | 30.4 (0.91) | 28.7 (0.7) | 0.09 |
| Mitral ALL:LVEDD ratio | 0.66 (0.03) | 0.68 (0.01) | 0.54 |
| Mean mitral PLL, mm | 19.1 (0.8) | 15.0 (0.5) | <0.001 |
| Mitral PLL:LVEDD ratio | 0.41 (0.02) | 0.36 (0.01) | 0.02 |
| ECG Q waves | 50% | 27% | 0.36 |
| ECG ST depression | 50% | 0% | 0.01 |
| Any ECG abnormality | 75% | 52% | 0.40 |
| Troponin T, pg/mL | 3.9 (1.0) | 2.5 (0.4) | 0.20 |
| NT-proBNP, pg/mL | 208 (72) | 57 (13) | 0.04 |
| PICP, μg/L | 139 (17) | 122 (4) | 0.35 |
| CMR crypts, % present | 50% | 7% | 0.07 |
Values represent adjusted means and standard errors unless otherwise indicated. Age, sex and causal gene were compared using a t-test or Fisher exact test. ECG measures were adjusted for age and family relations except for ST depression where the 0% rate required use of Fisher's exact test. All other clinical measures were adjusted for age, gender, genotype, diltiazem treatment, and family relations.
ALL, anterior leaflet length; CMR, cardiac magnetic resonance; E′, tissue Doppler early myocardial relaxation velocity; HCM, hypertrophic cardiomyopathy; LVEDD, left ventricular end-diastolic diameter; LVEF, left ventricular ejection fraction; Max LVWT, maximal left ventricular wall thickness; NT-proBNP, N-terminal propeptide of B-type natriuretic peptide; PICP, C-terminal propeptide of procollagen type I; PLL, posterior leaflet length.